006.Kubernetes二進制部署ETCD

一 部署ETCD集羣

1.1 安裝ETCD

etcd 是基於 Raft 的分佈式 key-value 存儲系統，由 CoreOS 開發，經常使用於服務發現、共享配置以及併發控制（如 leader 選舉、分佈式鎖等）。kubernetes 使用 etcd 存儲全部運行數據。

  1 etcd 是基於 Raft 的分佈式 key-value 存儲系統，由 CoreOS 開發，經常使用於服務發現、共享配置以及併發控制（如 leader 選舉、分佈式鎖等）。kubernetes 使用 etcd 存儲全部運行數據。
  2 [root@k8smaster01 ~]# cd /opt/k8s/work
  3 [root@k8smaster01 work]# wget https://github.com/coreos/etcd/releases/download/v3.3.13/etcd-v3.3.13-linux-amd64.tar.gz
  4 [root@k8smaster01 work]# tar -xvf etcd-v3.3.13-linux-amd64.tar.gz

1.2 分發ETCD

  1 [root@k8smaster01 ~]# cd /opt/k8s/work
  2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh
  3 [root@k8smaster01 work]# for master_ip in ${MASTER_IPS[@]}
  4   do
  5     echo ">>> ${master_ip}"
  6     scp etcd-v3.3.13-linux-amd64/etcd* root@${master_ip}:/opt/k8s/bin
  7     ssh root@${master_ip} "chmod +x /opt/k8s/bin/*"
  8   done

1.3 建立etcd證書和密鑰

  1 [root@k8smaster01 ~]# cd /opt/k8s/work
  2 [root@k8smaster01 work]# cat > etcd-csr.json <<EOF
  3 {
  4     "CN": "etcd",
  5     "hosts": [
  6     "127.0.0.1",
  7     "172.24.8.71",
  8     "172.24.8.72",
  9     "172.24.8.73"
 10   ],
 11     "key": {
 12         "algo": "rsa",
 13         "size": 2048
 14     },
 15     "names": [
 16         {
 17             "C": "CN",
 18             "ST": "Shanghai",
 19             "L": "Shanghai",
 20             "O": "k8s",
 21             "OU": "System"
 22         }
 23     ]
 24 }
 25 EOF
 26 #建立etcd的CA證書請求文件

解釋：

hosts 字段指定受權使用該證書的 etcd 節點 IP 或域名列表，須要將 etcd 集羣的三個節點 IP 都列在其中。

  1 [root@k8smaster01 ~]# cd /opt/k8s/work
  2 [root@k8smaster01 work]# cfssl gencert -ca=/opt/k8s/work/ca.pem \
  3 -ca-key=/opt/k8s/work/ca-key.pem -config=/opt/k8s/work/ca-config.json \
  4 -profile=kubernetes etcd-csr.json | cfssljson -bare etcd	#生成CA密鑰（ca-key.pem）和證書（ca.pem）

1.4 分發證書和私鑰

  1 [root@k8smaster01 ~]# cd /opt/k8s/work
  2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh
  3 [root@k8smaster01 work]# for master_ip in ${MASTER_IPS[@]}
  4   do
  5     echo ">>> ${master_ip}"
  6     ssh root@${master_ip} "mkdir -p /etc/etcd/cert"
  7     scp etcd*.pem root@${master_ip}:/etc/etcd/cert/
  8   done

1.5 建立etcd的systemd

  1 [root@k8smaster01 ~]# cd /opt/k8s/work
  2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh
  3 [root@k8smaster01 work]# cat > etcd.service.template <<EOF
  4 [Unit]
  5 Description=Etcd Server
  6 After=network.target
  7 After=network-online.target
  8 Wants=network-online.target
  9 Documentation=https://github.com/coreos
 10 
 11 [Service]
 12 Type=notify
 13 WorkingDirectory=${ETCD_DATA_DIR}
 14 ExecStart=/opt/k8s/bin/etcd \\
 15   --data-dir=${ETCD_DATA_DIR} \\
 16   --wal-dir=${ETCD_WAL_DIR} \\
 17   --name=##MASTER_NAME## \\
 18   --cert-file=/etc/etcd/cert/etcd.pem \\
 19   --key-file=/etc/etcd/cert/etcd-key.pem \\
 20   --trusted-ca-file=/etc/kubernetes/cert/ca.pem \\
 21   --peer-cert-file=/etc/etcd/cert/etcd.pem \\
 22   --peer-key-file=/etc/etcd/cert/etcd-key.pem \\
 23   --peer-trusted-ca-file=/etc/kubernetes/cert/ca.pem \\
 24   --peer-client-cert-auth \\
 25   --client-cert-auth \\
 26   --listen-peer-urls=https://##MASTER_IP##:2380 \\
 27   --initial-advertise-peer-urls=https://##MASTER_IP##:2380 \\
 28   --listen-client-urls=https://##MASTER_IP##:2379,http://127.0.0.1:2379 \\
 29   --advertise-client-urls=https://##MASTER_IP##:2379 \\
 30   --initial-cluster-token=etcd-cluster-0 \\
 31   --initial-cluster=${ETCD_NODES} \\
 32   --initial-cluster-state=new \\
 33   --auto-compaction-mode=periodic \\
 34   --auto-compaction-retention=1 \\
 35   --max-request-bytes=33554432 \\
 36   --quota-backend-bytes=6442450944 \\
 37   --heartbeat-interval=250 \\
 38   --election-timeout=2000
 39 Restart=on-failure
 40 RestartSec=5
 41 LimitNOFILE=65536
 42 
 43 [Install]
 44 WantedBy=multi-user.target
 45 EOF

解釋：

WorkingDirectory、--data-dir：指定工做目錄和數據目錄爲 ${ETCD_DATA_DIR}，需在啓動服務前建立這個目錄；

--wal-dir：指定 wal 目錄，爲了提升性能，通常使用 SSD 或者和 --data-dir 不一樣的磁盤；

--name：指定節點名稱，當 --initial-cluster-state 值爲 new 時，--name 的參數值必須位於 --initial-cluster 列表中；

--cert-file、--key-file：etcd server 與 client 通訊時使用的證書和私鑰；

--trusted-ca-file：簽名 client 證書的 CA 證書，用於驗證 client 證書；

--peer-cert-file、--peer-key-file：etcd 與 peer 通訊使用的證書和私鑰；

--peer-trusted-ca-file：簽名 peer 證書的 CA 證書，用於驗證 peer 證書。

1.6 修改systemd相應地址

  1 [root@k8smaster01 ~]# cd /opt/k8s/work
  2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh
  3 [root@k8smaster01 work]# for (( i=0; i < 3; i++ ))
  4   do
  5     sed -e "s/##MASTER_NAME##/${MASTER_NAMES[i]}/" -e "s/##MASTER_IP##/${MASTER_IPS[i]}/" etcd.service.template > etcd-${MASTER_IPS[i]}.service
  6   done

1.7 分發etcd systemd

  1 [root@k8smaster01 ~]# cd /opt/k8s/work
  2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh
  3 [root@k8smaster01 work]# for master_ip in ${MASTER_IPS[@]}
  4   do
  5     echo ">>> ${master_ip}"
  6     scp etcd-${master_ip}.service root@${master_ip}:/etc/systemd/system/etcd.service
  7   done

二 啓動並驗證

2.1 啓動ETCD

  1 [root@k8smaster01 ~]# cd /opt/k8s/work
  2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh
  3 [root@k8smaster01 work]# for master_ip in ${MASTER_IPS[@]}
  4   do
  5     echo ">>> ${master_ip}"
  6     ssh root@${master_ip} "mkdir -p ${ETCD_DATA_DIR} ${ETCD_WAL_DIR}"
  7     ssh root@${master_ip} "systemctl daemon-reload && systemctl enable etcd && systemctl restart etcd " &
  8   done

2.2 檢查ETCD啓動

  1 [root@k8smaster01 ~]# cd /opt/k8s/work
  2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh
  3 [root@k8smaster01 work]# for master_ip in ${MASTER_IPS[@]}
  4   do
  5     echo ">>> ${master_ip}"
  6     ssh root@${master_ip} "systemctl status etcd|grep Active"
  7   done

2.3 驗證服務狀態

  1 [root@k8smaster01 ~]# cd /opt/k8s/work
  2 [root@k8smaster01 work]# source /opt/k8s/bin/environment.sh
  3 [root@k8smaster01 work]# for master_ip in ${MASTER_IPS[@]}
  4   do
  5     echo ">>> ${master_ip}"
  6     ETCDCTL_API=3 /opt/k8s/bin/etcdctl \
  7     --endpoints=https://${master_ip}:2379 \
  8     --cacert=/etc/kubernetes/cert/ca.pem \
  9     --cert=/etc/etcd/cert/etcd.pem \
 10     --key=/etc/etcd/cert/etcd-key.pem endpoint health
 11   done

2.4 查看ETCD當前leader

  1 [root@k8smaster01 ~]# source /opt/k8s/bin/environment.sh
  2 [root@k8smaster01 ~]# ETCDCTL_API=3 /opt/k8s/bin/etcdctl \
  3   -w table --cacert=/etc/kubernetes/cert/ca.pem \
  4   --cert=/etc/etcd/cert/etcd.pem \
  5   --key=/etc/etcd/cert/etcd-key.pem \
  6   --endpoints=${ETCD_ENDPOINTS} endpoint status

如上所示，當前ETCD集羣的leader爲172.24.8.71。